Design of Electro-optical Vibrometer for On-Machine Metrology in Hybrid Single-Point Diamond Turning

Abstract

Single-point diamond turning (SPDT) is a machining process with high levels of profile accuracy and nanometric surface characteristics. SPDT is a leading technology in advanced manufacturing of ultra-precision optical components for critical applications. Different efforts have been undertaken to improve the cutting condition and optimize the machining parameters during SPDT. The implementation of on-machine metrology system (OMMS) has helped to improve the outcomes of SPDT in terms of machined profile accuracy and understand the effects of various processing parameters on optical surface generation. OMMS could be implemented in the hybrid SPDT platforms to effectively improve machining conditions by measuring and diagnosing, and providing testing procedures. Different sensors and principles have been used in the design and development of OMMS including laser-based optical systems. However, measuring the micrometric and nanometric parameters during diamond cutting is difficult to achieve at relatively low resolutions. The purpose of this study is to design and simulate an electro-optical vibrometer (EOV) for measuring machine-tool and workpiece vibration during the SPDT process. The proposed EOV has the capability of measuring, monitoring, and analyzing the vibration characteristics in different machining conditions. In addition, the designed system can communicate with the main control units of the hybrid SPDT platforms. Design specifications and simulation results have shown that the implemented mechanism is functional and has met requirements for a successful profiling vibrometry system that can be employed on SPDT machines.